Informationssøgning og informationsgenfinding

Peer-to-peer(P2P)computingiscurrentlyattractingenormousmediaattention, spurred by the popularity of ?le sharing systems such as Napster, Gnutella and Morpheus. In P2P systems a very large number of autonomous computing nodes (the peers) pool together their resources and rely on each other for data and services. The wealth of business opportunities promised by P2P networks has gene- ted much industrial interest recently, and has resulted in the creation of various industrial projects, startup companies, and special interest groups. Researchers from distributed computing, networks, agents and databases have also become excited about the P2P vision, and papers tackling open problems in this area have started appearing in high-quality conferences and workshops. Much of the recent research on P2P systems seems to be carried out by - search groups with a primary interest in distributed computation and networks. This workshop concentrated on the impact that current database research can have on P2P computing and vice versa. Although researchers in distributed data structures and databases have been working on related issues for a long time, the developed techniques are simply not adequate for the new paradigm.

The Information Management Systems group at the University of Padua, led by Maristella Agosti, has been a major contributor to information retrieval and digital libraries for nearly twenty years.This group has produced some of Italy's best-known IR researchers, whose work spans a broad range of topics, as the papers in this book demonstrate. One of the goalsof the IR book series is to highlight the work of academic research centers in our ?eld, in order to balancetheperceptionthateveryoneinIRworksforasearchenginecompany. One of the best aspects of our ?eld is that, as academic researchers, we can work with new graduate students and collaborate with companies to ensure that our research has direct impact on systems that people use every day. The Padua group is typical in this respect, and has been involved in a series of collaborations and major European projects over the years. I hope this volume inspires graduate students to pursue research in IR, and I encourage other research groups to contribute their own collections of papers. Amherst, Massachusetts. July 2007. W. Bruce Croft Preface The Information Management Systems (IMS) Research Group was formed in the Department of Information Engineering (formerly Department of El- tronicsandComputer Science)ofthe UniversityofPadua,Italy,in1987when the department was established. The group activities are concerned with the design,modelingandimplementationofadvancedinformationretrievaltools- such as search engines - and digital library systems.

The area of similarity searching is a very hot topic for both research and c- mercial applications. Current data processing applications use data with c- siderably less structure and much less precise queries than traditional database systems. Examples are multimedia data like images or videos that offer query by example search, product catalogs that provide users with preference based search, scientific data records from observations or experimental analyses such as biochemical and medical data, or XML documents that come from hetero- neous data sources on the Web or in intranets and thus does not exhibit a global schema. Such data can neither be ordered in a canonical manner nor meani- fully searched by precise database queries that would return exact matches. This novel situation is what has given rise to similarity searching, also - ferred to as content based or similarity retrieval. The most general approach to similarity search, still allowing construction of index structures, is modeled in metric space. In this book. Prof. Zezula and his co authors provide the first monograph on this topic, describing its theoretical background as well as the practical search tools of this innovative technology.

Chapters ¿No. 10 and No. 21¿ are available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

Question answering (QA) systems on the Web try to provide crisp answers to information needs posed in natural language, replacing the traditional ranked list of documents. QA, posing a multitude of research challenges, has emerged as one of the most actively investigated topics in information retrieval, natural language processing, and the artificial intelligence communities today. The flip side of such diverse and active interest is that publications are highly fragmented across several venues in the above communities, making it very difficult for new entrants to the field to get a good overview of the topic. Through this book, we make an attempt towards mitigating the above problem by providing an overview of the state-of-the-art in question answering. We cover the twin paradigms of curated Web sources used in QA tasks trusted text collections like Wikipedia, and objective information distilled into large-scale knowledge bases. We discuss distinct methodologies that have been applied to solve the QA problem in both these paradigms, using instantiations of recent systems for illustration. We begin with an overview of the problem setup and evaluation, cover notable sub-topics like open-domain, multi-hop, and conversational QA in depth, and conclude with key insights and emerging topics. We believe that this resource is a valuable contribution towards a unified view on QA, helping graduate students and researchers planning to work on this topic in the near future.

The availability of geographic and geospatial information and services, especially on the open Web has become abundant in the last several years with the proliferation of online maps, geo-coding services, geospatial Web services and geospatially enabled applications. The need for geospatial reasoning has significantly increased in many everyday applications including personal digital assistants, Web search applications, local aware mobile services, specialized systems for emergency response, medical triaging, intelligence analysis and more. Geospatial Semantics and the Semantic Web: Foundations, Algorithms, and Applications, an edited volume contributed by world class leaders in this field, provides recent research in the theme of geospatial semantics. This edited volume presents new information systems applications that have potential for high impact and commercialization. Also, special effort was made by the contributors to focus on geospatial ontology development, related standards, geospatial ontology alignment and integration, and algorithmic techniques for geospatial semantics. Case studies and examples will be provided throughout this book as well as possibilities for future research.

This book constitutes the refereed proceedings of the 15th IAPR International Workshop on Document Analysis Systems, DAS 2022, held in La Rochelle, France, in May 2022.The full papers presented were carefully reviewed and selected from numerous submissions addressing key techniques of document analysis.

This two volume set LNCS 9049 and LNCS 9050 constitutes the refereed proceedings of the 20th International Conference on Database Systems for Advanced Applications, DASFAA 2015, held in Hanoi, Vietnam, in April 2015. The 63 full papers presented were carefully reviewed and selected from a total of 287 submissions. The papers cover the following topics: data mining; data streams and time series; database storage and index; spatio-temporal data; modern computing platform; social networks; information integration and data quality; information retrieval and summarization; security and privacy; outlier and imbalanced data analysis; probabilistic and uncertain data; query processing.